Steam-generator



(No Model.)

' N. T. P1TK1N.

STEAM GENERATOR.

Patented Mey 19,1891.

UNITED STATES PATENT OFFICE.

NORMAN T. PITKIN, OF HARTFORD, CONNECTICUT.

' STEAM-G EN ERATOR.

SPECIFICATION forming part of Letters Patent N o. 452,388, dated May 19, 1891. Application filed February 4, 1891. Serial No. 380,157. (No model.)

T0 all whom it may concern.-

Be it known that I, NORMAN T. PITKIN, a citizen of the United States, residing at Hartford, in the county of Hartford and State of Connecticut, have invented certain new and useful Improvements in `Steam-Generators, of which the followingr is a full, clear, and eX- act specification. 1 l

The invention relates to vertical tubular iire-box steam-boilers, and the object is to increase the efficiency and strength of such boilers without adding to their size Vor cost.

To this end the invention consists in such a boiler having a novel arrangement of flues, whereby an increased circulation is insured, a direct easy vertical liberation of steam from around the heated iiues into an enlarged central steam-space is permitted, and a large central outlet from the steam-chamber is provided; also in the arrangement and shape of the crown-sheets of the fire-box and steamchamber, which adds to the strength of the construction and reduces the liability of leakage around the ends of the peculiarly-arranged iiues which pass from the combustionchamber to the smoke-box above.

Referring to the accompanying drawings, Figure l. is an elevation of the boiler. Fig. 2 is a central section of the same. Fig..3 is a cross-section on plane denoted by the linen@ o0, and Fig. 4C is a cross-section on plane denoted byline y y.

In the views, the letter a indicates the shell or jacket of a vertical tubular boiler, which ismade of the usual metal in the customary manner. Inside of the shell, near the bottom, by suitable stays, is supported the iire-box Z), having openings copposite the stolze-doors a and any desirable form of grate el above an ash-pit e, to which an opening a2 through the shell is made. The side Walls bf of the fireboX b, which is somewhat smaller in diameter than the shell a, are preferably parallel with the sides of the shell, leaving the desired Water-legs f around the fire-box, while the top or crown-sheet b2 above the combustion-chamber g is slightly conveXed or domed. 4The top or crown-sheet a8 of the shell or Water-jacket a above the steam-chamber s is also slightly convexed or domed, preferably being curved upon the arc of a circle that is concentric with the circle upon which the crown-sheet b2 of the re-boX is formed. The lues h,which are grouped together and pass through the crown-sheet b2 above the combustion-chamber at even distances apart, filling this crownsheet practically full, diverge from the axis of the boiler as they rise, leavinga large space between the center flues at the point where they reach the crown-sheet a3 above the water and steam-chambers, through which, however, they pass at the samedistances apart from each other at which they left the bottom crown-sheet Z22-that is, those flues which are upon the same radii are parallel and all inoline from the center or axis of the boiler, leaving a larger space at the top between the center flues than anywhere else for the collection of the steam.

Above the top crown-sheet a is located the usual smokebox g', from which any ordinary outlet is made for the escape of the products of combustion to a chimney. From the cen ter of the crown-sheet a3 at the top of the steam-chamber above the open space left at the center by the diverging iiues a pressurepipe z' for live steam leads through the smokeboX to any form of safety-valve j, having an. outlet for connection with an engine and a discharge for the relief of any excess pressure generated. An inlet-pipe passes through the shell or head at any suitable point to any desired position in the interior of the boiler, and any common form of water and steam gages may be attached, as desired, at suitable points. By this arrangement and location of the diverging lues for the passage of the products of combustion and heated gases through the water-chamber an enlarged space for the formation of the steam and necessary ebullition of the Water is provided at the center of the chamber, which insures a rapid formation of vapor and an increased circulation down the cooler sides of the shell and up at the center into the enlarged space. The iiames and heated gases in passing through the inclined flues come in contact with and more directly impinge upon their upper surfaces and heat them to a higher temperature than when passing through vertical flues without a tendency to impinge more on one side than the other, and the steam generated can rise vertically direct from the upper heated 'surface of the inclined flues into the central steam-space easier than from around vertical fines. The Crown-sheet over the fire-box is llled with ilues, all of which extend through the upper crown-sheet, however, leaving the center of the latter clear for a large livesteam outlet. These erown-sheets at the top and bottom are preferably formed upon ooneentrie circles, and the [lues lie on radii of these circles, so that the lues pass through the crown-sheets at approximately right angles to the heads, so that the joints may be tightly tted and cannot leak, while the oonvexing of the crowns gives them additional sirengthto resist the pressure ofthe steam or a vacuum, should one be formed when the steam is allowed to condense. Sediment is unlikely to settle upon the lower rounded crown-sheet, but is Washed off into the water-legs around the {ire-box, from which it can be removed.

NORMAN T. PITKIN.

\Vit11,esses:

HARRY R. WILLIAMS, ARTHUR B. JENKINS. 

